The majority of musculoskeletal patients attend with Lumbo-Pelvic and Hip dysfunction complaining of difficulty during walking and running. Clinicians commonly use weight bearing tests to examine the components of walking and running but these tests use postures and movements that are different to those found during gait. Few studies have examined the relationship between these tests and gait. The aim of this study was to investigate the validity of the Trendelenburg Test, Single Leg Squat and Corkscrew Test as measures of dynamic stability of the Lumbo-Pelvic and Hip region in healthy participants and professional football players during gait. This was a laboratory based study using an experimental, repeated measures design. 18 full time professional football players and 14 healthy participants were recruited. Movement data was captured using a ten camera system using the CAST technique. This study found that for walking there should be observable movement of all the regions and in all planes except at the: lumbar spine; thoracic spine ; trunk in the sagittal plane and lumbar spine; pelvis in the coronal plane. For running there should be observable movement of all the regions and planes. Recommendations are made for changes in the interpretation of the Trendelenburg Test and Single Leg Squat. New values for the interpretation of the Corkscrew Test were also established. Professional football players exhibited differences in their movement patterns at the hip, pelvis and trunk when compared to the healthy participants. Using the Corkscrew and Single Leg Squat Tests in combination allows clinicians to comprehensively examine the sagittal and coronal plane range of movement of the lumbar and thoracic spine relevant to walking. Similar movements occurred during the tests and both walking and running, but the similarities occurred only in specific regions and planes. Hence the tests were found to be task, region and plane specific. A greater understanding of the clinical tests and their relationship to gait may help clinicians to implement evidence based examination, sub-classify and treat Lumbo-Pelvic and Hip dysfunction. This will be of greatest use when examining and treating populations who have been found to have Lumbo-Pelvic and Hip dysfunction such as young males and professional football players.